We all love Android (err, well, okay. Many of us do). I like it. I also like the number of stuff I get for free. Having to spend bucks on an app I’d be trying for a bit is absolutely the kind of stuff I don’t like. Sometimes, if I find the app not worth buying, although I’d be using it daily, I try to find other free alternatives.

But, Android app developers have also been offering ad-enabled versions, with the same set of features as the paid version (many of them like to call it as ‘Donate version’, which is absolute BS, in my opinion). Which is, most of the times, a life savior. But.. it’s not as good as it sounds.

A computer scientist at Purdue University, Indiana – Abhinav Pathak, along with his colleagues, developed an app to analyse app energy usages. And the revelations are quite… surprising? I don’t know. It should be common sense, but the severity of the results is shocking. Popular apps (apps and games, both being referred here as apps) like Angry Birds spend only about 20 percent of the energy for the functioning of the game, and the rest is spent on ads – uploading user data and downloading relevant ads.

While I understand that developers need to make some money, I find it ridiculous how they don’t try to optimize their code. For example, if you’re using an ad-enabled app, the app will download the ad over internet (mobile data or wifi) and yet keep the connection open for 10 seconds after it’s done doing so. That gets added up and costs a lot of battery drain. 30 percent, for instance.

An app which would use about 10% of battery if it shows ads, an ad-free version would use up just 3%. That’s a lot. Also, Abhinav and his team plan to release a Windows Phone version as well. I’m expecting similar (or worse) results.

So, will you use an ad-enabled app after reading this? Or would you go buy the app? Another simple alternative you have is to root your Android and install an ad-blocker. Although you won’t be able to save all of that 70% juice, you should still be able to save a lot. Not an ideal solution, but you know, better than nothing.